-
25.
Aquifers
Subjects
Hydrogeology
-
26.
Archaeological geology
Subjects
ArchaeologyGeology
-
27.
Archean
Subjects
Precambrian
-
28.
Area measurement
Subjects
Figure of the EarthMathematical geography
-
29.
Arenària
Subjects
-
30.
Arenites
Subjects
Sedimentary rocks
-
31.
Arid regions
Subjects
IrrigationClimatic zonesCrop zones
-
32.
Arid soils
Subjects
Soils
-
33.
Artificial reefs
Subjects
ReefsFishing
-
34.
Artròpodes fòssils
Subjects
Fossil invertebrates
-
35.
Asbestos
Subjects
Building materials
-
36.
Atmosphere
Subjects
-
37.
Atmospheric chemistry
Subjects
AtmospherePhysical and theoretical chemistry
-
38.
Atmospheric circulation
Subjects
ClimatologyWinds
-
39.
Atmospheric electricity
Subjects
Weather
-
40.
Atmospheric greenhouse effect
Subjects
-
41.
Atmospheric ozone
Subjects
Atmospheric chemistryOzone
-
42.
Atmospheric physics
Subjects
Geophysics
-
43.
Atmospheric pollution
Subjects
PollutionEnvironmental health
-
44.
Atmospheric pressure
Subjects
MeteorologyPressureWeather
-
45.
Atmospheric radiation
Subjects
-
46.
Atmospheric temperature
Subjects
MeteorologyWeather
-
47.
Atmospheric thermodynamics
Subjects
AtmosphereThermodynamics
-
48.
Atmospheric turbulence
Subjects
AtmosphereAtmospheric circulationTurbulence